Commercial applications of microbially derived cellulose have only recently been explored. Cellulose biosynthesis by the bacterium Acetobacter xylinum has distinctive advantages over traditional sources: no delignification is required following harvest; the product can be synthesized directly into an extremely strong non-woven "textile" of virtually any shape; the physical properties of the cellulose such as crystallinity, hydrophilicity, and degree of polymerization, can be controlled during synthesis; and, the cellulose can be produced from a wide variety of substrates. The ability to alter physical characteristics of the cellulose in situ may provide an efficient method for producing a broad array of value-added products. The development of a commercially feasible fermentation system for producing Acetobacter cellulose presents a significant technological challenge. Large-scale fermentation is complicated by a number of phenomena associated with the biology of acetic acid bacteria including strain instability, the synthesis of gluconic acid as a significant by-product, and poor oxygen diffusion through the cellulose product of this strictly aerobic bacterium. Pressure-cycle or dual hollow fiber (DHF) fermenters may eliminate or reduce many of the problems encountered in producing large quantities of microbial cellulose. Further commercialization of Acetobacter cellulose will depend upon the successful integration of various technical and economic elements including market requirements, end-product characteristics, fermenter design and operating conditions, cost and availability of substrates, and geographic location. The ultimate promise of Acetobacter is the ability to take advantage of the rich scientific and technological knowledge base associated with it for the development of a commercial scale cell-free cellulose biosynthetic system. Such a system might allow the production of an even wider variety of cellulose based products with even greater efficiency, thus preserving valuable natural resources.

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